Heat puffing of a cured latex coated fabric of cotton and thermoplastic fibers



April 3, 19b5 R. w. BRANNOCK 3,

HEAT PUFFING OF A CURED LATEX COATED FABRIC 0F COTTON AND THERMOPLASTIC FIBERS Filed March 1, 1960 22 21 I 'I I| Q i it i 1 "w I l \{I 5* mg" 5% E INVENTOR U. N

Pusan; MB/mwA/ocK JWQ M/KMM ATTORNEYS United States Patent HEAT PUFFING 0E A (IURED LATEX GOATED FABRIC 0F COTTON AND THERMOPLASTHC I FIBERS Russell W.- Brannock, Burlington, N.C., assignor to Burlington Industries, Inc., Greensboro,- N.C., a corpora tionof Delaware Filed Mar. 1, 1960, Se r.; No. 12,019 13 Claims. (Cl. 264-324) This invention relates to the. art of manufacturing decorative fabrics. More particularly, this invention is directed tov a novel process for the production of decorative fabrics having three dimensional contoured surfaces, and specifically provides a process for enhancing such threedimensional effects. 7

The art of weaving: fabrics to provide a product having a contoured irregular surface is well known. In some instances, the three-dimensionality of the surface is obtained primarily in the weaving technique which is employed. In other instances, a contoured surface is produced by either selectively lengthening part of the fibers in the woven fabric or by selectively shrinking part of the fibers in the woven fabric. Frequently, these processes involve the use of a pre-stres sed fiber, i.e. one which has beenstretched and by a subsequent treatment returns to its original un-stressed linear dimensions. Processes for preparing fabrics having a contoured surface in this manner generally employ a typical shrinkage operation, i.e. with a water spray which may have in addition wetting agents and detergents or other materials such as salts in the water solution. In some instances, the fabric has additionally been impregnated with such a solution having therein a resinous wetting agent.

It is an obiect of this invention to provide a technique of forming an increased puffing or lofted three-dimensional effect as a resultof the treatment of one side of the fabric withwa non-wetting latex or other resinous material which has particular characteristics, and brings about improved enhanced three-dimensional effects in subsequent drying and heat-treating operations.

It isa further object of this invention to produce a fabric having the desired contoured or three-dimensional effects as a result of the action of the resin coating in combination with a subsidiary shrinkage of at least a portion of the fibers in the fabric. 7

Broadly stated, the objects of the invention are achieved by spraying one side of a woven fabric, i.e. the underside, with an aqueous latex composition, thereafter steaming the fabric to assist its relaxation, and then drying and heattreating the fabric in the completely relaxed state. Depending on the fibers present in the fabric, a selective shrinkage of a portion thereof may take place during the drying and heat treating operations. The success of the invention is due, to a significant extent, in the feature of maintaining the fabric in the fully relaxed condition throughout the drying and heat-treating operations. The manner in which this is accomplished and other preferred aspects of the invention are hereinafter described.

For coating the fabric, latex solutions of various viscosities may be used provided the viscosity is such that it will not strike through to the upper surface of the fabric. Generally, the coatings employed in this invention exhibit, after the drying and heat treatment, a whitening of the fabric on the underside thereof. This effect is undesirable on the upper or outer side and it has been found that, if the latex used herein has a viscosity between about 900 and 300 cps., whitening of the upper or outer side of the fabric can be avoided. The solids content of the latex solution can be varied depending, for example, upon the resin used, but to obtain a coating which will 3,178,498 Patented Apr. 13, 1955 be effective in producing an enhanced three-dimensional effect, it is usually desirable to use a latex mixture having a resin solids content between 10 and 50%, by weight. Within this range, the subsequent heat treatment provides optimum surface effects in conjunction with desirable drape, hand and feel characteristics.

The latex formulations which are particularly adapted for use in the present invention include those formed from synthetic rubbers, such as GR-S rubber (butadi'enestyrene rubber) and acrylic rubbers, and other polymeric materials, such as polyvinyl chlorides and polyvinyl acetates. It will be understood that conventional vulcanizat'ion ingredients, antioxidants and loading agents to reduce tackiness may also be incorporated into the latex mixture in the usual manner of formulating latex coating. materials. In addition it may be desirable to incorporate a conventional thickener to obtain the necessary viscosity for the mixture. Particularly desirable as thickeners are the sodium acrylat'e thickeners. When an acrylic rubber is employed, it is usually preferred to use a latex formula having a 45 to 50% solids content. On the other hand, when a GR-S latex formula is used, a solids contento'f about 25% is preferred. Similar solids contents within the indicated range of about 10 to 50% may be used for other polymeric materials.

The fabrics treated in accordance with the present process may already include a lofted or otherwise corit'oured surface resulting from the' weaving process, as by the use of cotton fillers. The fabric may be woven from various fibers and may contain, for instance, polyethylene, rayon, nylon, cotton and direct spun rayon, Saran, and Velon yarns, in the warp or otherwise; The process is particularly advantageous for use on niatel'asse fabrics but it can also be used on other rough textured, puffed or lofted fabrics, the three dimension'al effects being improvedin each instance by the operation of the present invention as compared to conventional processes. In fact, by using the present process with a single shuttle single beam matelasse weave, the effects obtained are comparable to those which result from the use of two beams and special fillings using conventional techniques.

Generally speaking, the yarn denier and sley of the fabric can be varied over a wide range according to the present invention. Typically, excellent effects are obtained using yarn deniers of the order of to 200 and a fabric having something of the order of l50'to 1'80" sley warps in the weave.

The amount of shrinkage which takes place in the fabric during the drying and heat treatment depends upon other operating factors, mainly the nature of the fibersinvolved and their characteristics in the fabric, and to a lesser extent on the latex used, the temperatures employed, etc. It has been observed, for instance, that with a single beam 150 sley 250 denier nylon warp and a cotton filling, the shrinkage was 2 .3 in the warpand 1.61% in the filling. With a sley 15 0 denier rayon warp single shuttle matelasse the shrinkage was about 2 /2% in the warp and the filling. With single beam 150 sley 150 denier rayon warps and cotton filling the shrinkage was about 3% of the warp and filling. The shrinkage with other types of fabrics has been about 3.8% in the warp and 1.3% in the filling. The overall process has, however, a relaxing effect on these fabrics which tends to eliminate shrinkage in the finished product after cutting and sewing.

The invention is diagrammatically illustrated in the accompanying drawing. As shown therein, the fabric F is fed from a supply roll '2 around guide rolls 4 and into spray box 6 where latex solution is applied to the backside of the fabric. From the spray box 6, the fabric is passed over a Wet steam unit 8 and then between a pair of rubber covered overfeed nip rollers 10 which lay the fabric onto an endless conveyor belt 12 at the inlet to oven 14. The overfeeding of the fabric onto belt 12 by means of the nip rollers ensures complete relaxation of the fabric during the drying and heat treating in oven 14. The nip rollers 10 may be adjustable to allow for variable degrees of overfeed and lofting. Heat is supplied to the oven by any suitable means 15, for example, steam coils circulating air through a duct system 16 including blower 18 and motor 20, as shown. The temperature in the oven is desirably maintained between 180 F. and 325 F. due to heat sensitivity of certain component yarns, such as Saran, Velon, polyethylene, etc. Desirably, the oven is insulated with e.g. 3" rock wool or the like to assist in temperature control.

After the heat treatment, the fabric leaving the oven is taken up as shown at 22 and may be plated down, relaxed on pallets or batched into rolls as desired.

As a typical illustration of operations according to the invention, a single matelasse fabric with single beam 150 sley 200 denier nylon warp and single shuttle cotton filling was finished by spraying its backside in spray box 6 with 25% solid GR-S latex formula, 4 ounces wet per linear yard. The fabric was then passed over a 36 unit of wet steam (designated by the numeral 8 in the drawing). Overfeed rollers 10 laid the fabric onto conveyor belt 12 travelling at yards per minute, to give complete relaxation of the fabric in the oven. Drying took place in the oven at 280 F. Using a single pass through a 20 oven, the drying time was about 20 seconds after which the fabric was batched in rolls up to 40 diameter faceout. It will be appreciated that the time of treatment in the oven may be varied over a wide range, typically .25 to 10 seconds, depending upon the temperature utilized and other operating factors. Similarly, the amount of latex applied to the fabric in spray box 6 can be varied depending upon the nature of the fabric, etc., with .0025 to .05 part by weight of latex (solids) per part of fabric typical.

Rayon warp matelasse can also be treated in the manner just illustrated. Similarly, fabrics comprising polyethylene, Velon (copolymer of vinylidene chloride and vinyl chloride) and Saran (vinylidene chloride polymer), among others, can be effectively treated in the manner described herein, preferably using drying temperatures between 180 F. and 220 F.

It will be appreciated that various modifications may be made in the invention described herein without deviating from the scope thereof as set forth in the accompanying claims wherein I claim:

1. A process for producing enhanced three-dimensional surface effects in a woven fabric having fibers of different heat shrinkable characteristics in the warp and weft selected from the group consisting of cotton fibers and synthetic thermoplastic fibers which comprises spraying the underside of said fabric in a relaxed state and prior to any significant heat shrinkage of said fabric with an aqueous latex mixture, treating the thus coated fabric with wet steam and then overfeeding said coated fabric into a heating zone wherein said fabric is dried and heattreated in the completely relaxed condition at a temperature between about 180 F. and about 325 F.

2. A process for producing enhanced three-dimensional surface effects in a woven fabric having fibers of different heat shrinkable characteristics in the warp and weft selected from the group consisting of cotton fibers and synthetic thermoplastic fibers which comprises spraying the underside of said fabric in a relaxed state and prior to any significant heat shrinkage therein with an aqueous latex mixture having a solids content between about 10 and 50% by weight, and a viscosity between about 900 and 3000 cps., treating the thus coated fabric with wet steam to further relax the same and then overfeeding said relaxed coated fabric into a heating zone wherein said fabric is heated to a temperature between about 180 to about 325 F., to dry and heat-treat the latex coating, whereby there is obtained a fabric having said pronounced three-dimensional surface characteristics.

3. The process of claim 2 wherein said latex is selected from the group consisting of butadienestyrene rubber, acrylic rubber, polyvinyl chloride and polyvinyl acetate.

4. The process of claim 1 wherein said fabric is a single shuttle single beam matelasse.

5. The process of claim 4 wherein said matelasse fiber has a nylon warp and a cotton weft.

6. The process of claim 4 wherein said matelasse fabric has a rayon cellulose acetate warp and a cotton weft.

7. The process of claim 4 wherein said matelasse fabric contains polymeric vinylidene chloride fibers.

8. The process of claim 4 wherein said matelasse fabric contains fibers comprising a copolymer of vinylidene chloride and vinyl chloride.

9. The process of claim 4 wherein said matelasse fabric contains polyethylene fibers.

10. The process of claim 2 wherein during said heating operation, at least part of the fibers in said fabric shrink.

11. The process which comprises coating in a relaxed state the underside of a single beam sley 200 denier nylon warp with cotton filling matelasse fabric, with an aqueous latex solution having a solids content between about 10 and 50% by weight and a viscosity between about 900 to 3000 cps., steaming said coated fabric to further relax the same, passing said relaxed coated fabric into a heating Zone whereby said fabric is heated to a temperature between about to 325 F., while in the completely relaxed condition wherein said fabric is dried and said warp is shrunk approximately 2.3% and said filling is shrunk approximately 1.6%.

12. The process of claim 11 wherein said latex solution comprises 25 solid synthetic butadiene-styrene rubber latex and said fabric is heated in said zone to a temperature of about 280 F.

13. The process of claim 2 wherein from .0025 to 0.5 part by weight of latex solution is sprayed onto said fabric per parts of fabric.

References Cited in the file of this patent UNITED STATES PATENTS 2,450,948 Foster Oct. 12, 1948 2,539,301 Foster Jan. 23, 1951 2,574,200 Teague Nov. 6, 1951 2,737,701 Hubbard et a1. Mar. 13, 1956 2,771,661 Foster Nov. 27, 1956 2,977,664 Grajeck Apr. 4, 1961 

1. A PROCESS FOR PRODUCING ENHANCED THREE-DIMENSIONAL SURFACE EFFECTS IN A WOVEN FABRIC HAVING FIBERS OF DIFFERENT HEAT SHRINKABLE CHARACTERISTICS IN THE WRAP AND WEFT SELECTED FROM THE GROUP CONSISTING OF COTTON FIBERS AND SYNTHETIC THERMOPLASTIC FIBERS WHICH COMPRISES SPRAYING THE UNDERSIDE OF SAID FABRIC IN A RELAXED STATE AND PRIOR TO ANY SIGNIFICANT HEAT SHRINKAGE OF SAID FABRIC WITH AN 